Electric lamp.



G. L. VAN WART.

'BLBOTRIG' LAMP. APP`LIGATION FILD AUG. 3, 190B,

2 EHBETS-SHEET l.

T11/wwwa Patented 0013.12, 1909.

ELECTRIC LAMP. APPLIOATION rum) AUG. a. 190s.

"150i Hmmm enoteca: L. *fait wenn, Warnavrtnn, commencer.

ELECTRIC LAMP.

lpecileatlo'n of Letters Patent.

Patented Het. i?,

applicati@ ined august a, ieee. serial No. Maese.

g and State of Connecticut, have invented certain new and useful lmprovementsin @lectric Lamps, of which the following is a specication.

The present invention relates toimprove ments in electric lighting, and more particularly`to a novel lnueans whereby a current flowing through the individual lamps may be controlled'and the lamps caused to burn with various degrees of brilliancy.

. More specifically the invention resides in the provision of a base to which `an incandescent lam may be secured, a series of reL sistances being vcarried by thebase and novel means being provided for cutting any select ed number'of these resistances into the circuit with the lamp.

For a full understanding of the invention and the merits 'thereof and also to acquire a knowledge of the details of construction and the means for effecting the result, reference is to be had to the following description and accompanyin drawings, in which:

Figure l is a si e elevation of a lamp base constructedV4 in accordance with the invention. Fig. 2 is a longitudinal sectional view through the same. Fig. 3 is a similar view on a plane at right angles to that of Fig. 2. Fig. 4f is an enlarged horizontal sectional view on the linee-f4 of Fig. 2. Fig. 5 is a side elevation of one of the contact members. Fig. G ris an end view of the saine. Fig. Y is a detail view of the bolt to which the contact member at the base of the socket is attached.

Corresponding and like parts are referred to in the followinv description and indicated in all the views'ot the drawings by the saine reference characters.

Referring to the drawings, the numeral l designates the casing of the electric light base, the said casing heilig shown as having a substantially cylindrical formation and as closed at its opposite ends by means ofthe heads 2 and 3 which are held in position by the screws 4 and may be formed of any suitable insulating material such as porcelain. Secured to the outer face ot the head 3 is a socket 5 which is internally threadcl and is designed to engage an incandescent lamp in the usual manner. Surrounding the socket 5 and secured to the casing is a cap lever.

6, a layer 7 ot insulating material being disposed upon the inner tace ot the-cap the said insulating material fitting between the outer ends of the socket and the cap t y the ,ocket is=co1npletely insulated from the metallic portions of the electric light base. 'lfl'ie contact member 8 at the base the socket 5 is in the nature oi a'nut wliichpis threaded upon a bolt 9 passing through the head 53, the head of the bolt being slotted at 9 to receive the flattened extremity ot' wire l0, a set screw il being utilized for retaining 'the flattened end of the wire in position within the slot. An opening 12 is formed in the head 3 at one side of the socket. and extending' through this opening is a wire 13 vthe extremity ot which is secured to 'the socket 5 upon the exterior thereof.

Fitted over the opposite end of the casing is a cap ift which is formed With e rim lag, the said rim being spaced from the Vcasing and nei/ing the inner edge thereof extended inwardly and secured to the casing. central portion of the cap is provided with a sleeve l5 through which the feed Wires 16 pass, the said sleeve being formed of some insulating material such as hard rubber. A peripheral row ot' contacts 17 is provided upon the head 2 and these contacts are constituted in the present instance by the heads of .bolts 17 which extend through the head and are capped by the nuts i8. Resistance coils 19 are interposed between the various contacts l?, the extremities ot the resistance coils being secured to the bolts lla by means The titi' of the nuts 18. One of the end contact members li' ot the series has the wire lO secured thereto and the various contact-s are designed to he frictionally engaged by a lever 20 which is pi votally mounted upon a bolt 2l passing centrally through the head Q, washers 25 being placed above and below the The free end of the lever extended laterally at 20 so as to swing in the space between the casing l and the rim 14a or' the cap 14, and terminates in a linger-piece 2l ot some insulating" material.

spring plate is disposed immediately over the lever 2() for holding it in a yielding engagement with the various contact 11u-.my bers and this spring plate as shown on thc drawing formed with an arc-shaped portion 22a connected by the radial arms 22' to a tang 22 which is secured to the head 2 by suitable fastening members such as the screws 23. This tang is offset from the plane the plete so that the pleite optreed from the head end the niiddie erin 22 is deflected fondly so to extend over the head oli 'the bolt 21 without Coming into Contact therewith. @ne o the feed wires lo is oonneeted to one of the screws 23 end is in electrical connection with the spring late while the opposite feed Wire is connecte to e bindpost fifi which also engages the extremity of the wire 13. -v

When 'the lever 2() is swung to one side so that it does not engefe any of the contacts l? the circuit will be roken and no current will flow through the lomp engaged by the socket However, when 'the lever is moved into engagement with the opposite end contact of the serinel to that connected with the wire l0 all. of the resistanees 19 will be introduced into the circuit. with the lamp and the current flowing throu rh 'the lain p will be week rnd will only protuce :i week light. By moving the lever into engagement with the various contacts '17 any selected number oi the resistanees een be introduced into the circuit and. the lamp canned to burn at any desired degree of brillianey. Such e construction hns the advantage of lengtheningr the lite of the filament in 'the lamp ae the current must be turned on gradually and the full force ol' the current is not reused to pase Suddenly through the lainp. 'l`he invention has the further advantage oi enabling the individual lights to he burned either at their 'full caneeity or ata rediu'ed eandle power as desired.

Hoving thus described the invention,what is Claimed new is:

l. ln an electric light socket, the combination ol' u base, a series of contacts upon the base, resistanees interposed between thevarions contacts, e lever pivot/ed upon the base and designed to be swung into engagement. with any selected one of the contacts to introduce the desired number of resistences into the circuit, and a springf plate disposed over 'the lever und holding the saine in a yielding engagement with the contacts, the seid spring plate comprising an are shaped portion which is connected by radial arms to e. teng the tang being oll'set -from the plane of the remaining portion ot' the plate and secured to the base.

f2. ln an electric light socket, the eonibiuation ot' a cylindrical easing, heads applied to opposite ends of the oasinw, a socket upon one of the heads, a cap applied to the opposite end of the easing' and formed with a i which is spared i'roui the easing, n series ol' contacteupon the head at the said opposite end of the easing. l'en'islanees interposed between the variouhl rentar-is, and a lever pi\' otally mounted upon the head and adapted to be swung into engagement with an)v selected one ol the contat-ts to'introdluse the desired number ol' resistanees into the eirenin the end ol the lever bein;y extended lalwally and operating freely between the vyliiulrieal easingy and the rini of the cap.

ln testimony whereof l allirir my signature in presence olf two rfiiiussel 

